1. Field of the Invention
The present invention relates to an image figure editing system for enabling an efficient editing of figure elements of displayed image figures in a CAD/CAM system or a geographical data management system.
2. Description of the Background Art
There has been an increasing use of an image filing system such as an optical filing system equipped with an image scanner for the purpose of managing various handwritten or printed drawings such as maps and design specifications. In such an image filing system, an editing of figures in the drawing stored in terms of image data has been limited to simple addition and deletion using a pen and an eraser, as the manipulation of the figure elements given in terms of the image data has been severely limited compared with that of the ordinary CAD data in which individual figure elements are expressed in terms of numerically specified vector data. Similarly, in a CAD system using both the image data and the vector data, it has been impossible to treat the image data and the vector data equally.
As a consequence, in a conventional image filing system using the image data, the user is required to edit the figure elements given in terms of the image data very carefully to make appropriate additions and deletions in order to realize the desired editing operations such as rotation, expansion, contraction, and displacement of the figure elements, unlike the editing of the figure elements given in terms of the vector data in which the various editing operations mentioned above can be realized very easily by processing the vector data numerically.
Therefore, in a conventional image filing system using the image data, the user is required to distinguish the type of data in terms of which each figure is given and treat figures given in terms of different types of data differently at a time of editing the displayed drawing, which makes the editing operations on the image filing system to be extremely complicated to an extent that the levels of efficiency and accuracy achievable in the editing operations are inevitably limited to rather unsatisfactory levels.